RIYADH, March 28 (Reuters) - U.S. President Barack Obama reiterated the significance the United States places on its "strong relationship" with Saudi Arabia in talks with King Abdullah on Friday, a White House statement said.

It added that Washington and Riyadh were working together to address critical bilateral and regional issues, including "the crisis in Syria, preventing Iran from obtaining a nuclear weapon, counterterrorism efforts to combat extremism, and supporting negotiations to achieve Middle East peace".

Last year senior Saudi officials warned of a "major shift" away from Washington after bitter disagreements about its response to the "Arab Spring" uprisings, and policy towards Iran and Syria, where Riyadh wants more American support for rebels.

"In his meetings with King Abdullah in Riyadh, President Obama reiterated the significance the United States places on its strong relationship with Saudi Arabia, which has endured for over 80 years," the statement said.

Obama, making his first visit to Saudi Arabia since 2009, held two hours of talks with the king that aides had said would focus on Middle East peace, Iran and ways to strengthen moderate Syrian rebels.

The U.S. statement added that Saudi Arabia had been "a strong U.S. counterterrorism partner, particularly on disrupting Al Qaeda elements".

(Reporting by Jeff Mason; Editing by William Maclean, Sami Aboudi and Andrew Roche)